1. Field
The inventive concept relates to a semiconductor device, and more particularly, to a memory device to correct a defect cell generated after packaging is performed, a memory module and memory system including the memory device.
2. Description of the Related Art
After a semiconductor manufacturing process is performed, it is determined whether a memory device such as a dynamic random access memory (DRAM) is defect through tests. DRAM tests include a wafer test and a package test. In the wafer test, when defect memory cells are generated, the defect memory cells are replaced with redundant memory cells in a DRAM. However, when the defect memory cell is detected in the package test, it is impossible to replace the defect memory cell with a redundant memory cell, and thus the DRAM is finally determined to be defect. An error that occurs in the package test is likely to be a single bit error. In order to increase a manufacturing yield, there is a need to resolve a single bit error that occurs after packaging is performed.